Coupe or Sedan? Mercedes says the CLS-Class is a “coupe.” Problem is, the last time we checked, that designation was reserved for vehicles with just two doors. Therefore, we’ll call the CLS a sedan.

Before we get to the details of the 2006 Mercedes-Benz CLS-Class, let’s clear up a fundamental bit of confusion about what to call this shapely new four-door.

Visit the Mercedes-Benz website (www.mbusa.com) and you’ll find the CLS-Class described simply as a “coupe.” Problem is, the last time we checked, that designation was reserved for vehicles with just two doors, or vehicles with two primary doors and small secondary access panels to enter the rear seat. Therefore, we’ll call the CLS a sedan – a sleek and sexy one, but a sedan nonetheless.

The reasoning behind this semantic sleight-of-hand, as far as we can tell, is that the Mercedes marketing folks are trying to convey the idea that a coupe is more a state-of-mind than a physical description. Which, in a roundabout way, gets to the very essence of this new design: A car that combines the racy styling of a sports coupe with the real-world practicality of a sedan.

By positioning this new model as a four-door “coupe,” Mercedes has also tried to carve out a unique niche in an increasingly crowded luxury car field. The downside to this strategy, of course, is that it opens the CLS up to comparison with and competition from a much wider variety of excellent automobiles.

Competition batters the new 2006 Mercedes-Benz CLS-Class from two fronts. For starters, the rakish design puts the CLS up against a number of charismatic luxury coupes. And it’s easy to see how prospective buyers and current owners of two-seaters like Mercedes’ own SL500 and coupes with a highly impractical back seat like the Jaguar XK8 would find the CLS an attractive choice.

But no matter how much Mercedes would like to play to this sports coupe crowd, there’s no escaping the fact that this vehicle will be measured first and foremost against other high-end sports sedans. In a category like this, populated by the likes of the BMW 545i and Lexus GS 430, the CLS-Class clearly has its work cut out for it in trying to lure buyers away from some of the best looking and most luxurious performance-oriented four-doors on the market today.